it seems to me that the simplest solution would be a lifetime ban from cycling if caught. One to two years in not enough of a threat while a lifetime ban would be.
http://sg.news.yahoo.com/ap/20080718/tsp-cyc-tour-de-france-6e81073.html
http://sg.news.yahoo.com/ap/20080718/tsp-cyc-tour-de-france-6e81073.html
Officials at the Tour de France scrambled Thursday to limit fallout from the third doping bust in this year's race, which netted the biggest name yet: Italian star Riccardo Ricco, a winner of two stages.